// CodeMirror, copyright (c) by Marijn Haverbeke and others
// Distributed under an MIT license: http://codemirror.net/LICENSE

(function(mod) {
  if (typeof exports == 'object' && typeof module == 'object')
    // CommonJS
    mod(require('../../lib/codemirror'));
  else if (typeof define == 'function' && define.amd)
    // AMD
    define(['../../lib/codemirror'], mod);
  // Plain browser env
  else mod(CodeMirror);
})(function(CodeMirror) {
  var ie_lt8 =
    /MSIE \d/.test(navigator.userAgent) &&
    (document.documentMode == null || document.documentMode < 8);

  var Pos = CodeMirror.Pos;

  var matching = {
    '(': ')>',
    ')': '(<',
    '[': ']>',
    ']': '[<',
    '{': '}>',
    '}': '{<',
  };

  function findMatchingBracket(cm, where, config) {
    var line = cm.getLineHandle(where.line),
      pos = where.ch - 1;
    var afterCursor = config && config.afterCursor;
    if (afterCursor == null)
      afterCursor = /(^| )cm-fat-cursor($| )/.test(
        cm.getWrapperElement().className,
      );

    // A cursor is defined as between two characters, but in in vim command mode
    // (i.e. not insert mode), the cursor is visually represented as a
    // highlighted box on top of the 2nd character. Otherwise, we allow matches
    // from before or after the cursor.
    var match =
      (!afterCursor && pos >= 0 && matching[line.text.charAt(pos)]) ||
      matching[line.text.charAt(++pos)];
    if (!match) return null;
    var dir = match.charAt(1) == '>' ? 1 : -1;
    if (config && config.strict && dir > 0 != (pos == where.ch)) return null;
    var style = cm.getTokenTypeAt(Pos(where.line, pos + 1));

    var found = scanForBracket(
      cm,
      Pos(where.line, pos + (dir > 0 ? 1 : 0)),
      dir,
      style || null,
      config,
    );
    if (found == null) return null;
    return {
      from: Pos(where.line, pos),
      to: found && found.pos,
      match: found && found.ch == match.charAt(0),
      forward: dir > 0,
    };
  }

  // bracketRegex is used to specify which type of bracket to scan
  // should be a regexp, e.g. /[[\]]/
  //
  // Note: If "where" is on an open bracket, then this bracket is ignored.
  //
  // Returns false when no bracket was found, null when it reached
  // maxScanLines and gave up
  function scanForBracket(cm, where, dir, style, config) {
    var maxScanLen = (config && config.maxScanLineLength) || 10000;
    var maxScanLines = (config && config.maxScanLines) || 1000;

    var stack = [];
    var re = config && config.bracketRegex ? config.bracketRegex : /[(){}[\]]/;
    var lineEnd =
      dir > 0
        ? Math.min(where.line + maxScanLines, cm.lastLine() + 1)
        : Math.max(cm.firstLine() - 1, where.line - maxScanLines);
    for (var lineNo = where.line; lineNo != lineEnd; lineNo += dir) {
      var line = cm.getLine(lineNo);
      if (!line) continue;
      var pos = dir > 0 ? 0 : line.length - 1,
        end = dir > 0 ? line.length : -1;
      if (line.length > maxScanLen) continue;
      if (lineNo == where.line) pos = where.ch - (dir < 0 ? 1 : 0);
      for (; pos != end; pos += dir) {
        var ch = line.charAt(pos);
        if (
          re.test(ch) &&
          (style === undefined ||
            cm.getTokenTypeAt(Pos(lineNo, pos + 1)) == style)
        ) {
          var match = matching[ch];
          if ((match.charAt(1) == '>') == dir > 0) stack.push(ch);
          else if (!stack.length) return { pos: Pos(lineNo, pos), ch: ch };
          else stack.pop();
        }
      }
    }
    return lineNo - dir == (dir > 0 ? cm.lastLine() : cm.firstLine())
      ? false
      : null;
  }

  function matchBrackets(cm, autoclear, config) {
    // Disable brace matching in long lines, since it'll cause hugely slow updates
    var maxHighlightLen = cm.state.matchBrackets.maxHighlightLineLength || 1000;
    var marks = [],
      ranges = cm.listSelections();
    for (var i = 0; i < ranges.length; i++) {
      var match =
        ranges[i].empty() && findMatchingBracket(cm, ranges[i].head, config);
      if (match && cm.getLine(match.from.line).length <= maxHighlightLen) {
        var style = match.match
          ? 'CodeMirror-matchingbracket'
          : 'CodeMirror-nonmatchingbracket';
        marks.push(
          cm.markText(match.from, Pos(match.from.line, match.from.ch + 1), {
            className: style,
          }),
        );
        if (match.to && cm.getLine(match.to.line).length <= maxHighlightLen)
          marks.push(
            cm.markText(match.to, Pos(match.to.line, match.to.ch + 1), {
              className: style,
            }),
          );
      }
    }

    if (marks.length) {
      // Kludge to work around the IE bug from issue #1193, where text
      // input stops going to the textare whever this fires.
      if (ie_lt8 && cm.state.focused) cm.focus();

      var clear = function() {
        cm.operation(function() {
          for (var i = 0; i < marks.length; i++) marks[i].clear();
        });
      };
      if (autoclear) setTimeout(clear, 800);
      else return clear;
    }
  }

  var currentlyHighlighted = null;
  function doMatchBrackets(cm) {
    cm.operation(function() {
      if (currentlyHighlighted) {
        currentlyHighlighted();
        currentlyHighlighted = null;
      }
      currentlyHighlighted = matchBrackets(cm, false, cm.state.matchBrackets);
    });
  }

  CodeMirror.defineOption('matchBrackets', false, function(cm, val, old) {
    if (old && old != CodeMirror.Init) {
      cm.off('cursorActivity', doMatchBrackets);
      if (currentlyHighlighted) {
        currentlyHighlighted();
        currentlyHighlighted = null;
      }
    }
    if (val) {
      cm.state.matchBrackets = typeof val == 'object' ? val : {};
      cm.on('cursorActivity', doMatchBrackets);
    }
  });

  CodeMirror.defineExtension('matchBrackets', function() {
    matchBrackets(this, true);
  });
  CodeMirror.defineExtension('findMatchingBracket', function(
    pos,
    config,
    oldConfig,
  ) {
    // Backwards-compatibility kludge
    if (oldConfig || typeof config == 'boolean') {
      if (!oldConfig) {
        config = config ? { strict: true } : null;
      } else {
        oldConfig.strict = config;
        config = oldConfig;
      }
    }
    return findMatchingBracket(this, pos, config);
  });
  CodeMirror.defineExtension('scanForBracket', function(
    pos,
    dir,
    style,
    config,
  ) {
    return scanForBracket(this, pos, dir, style, config);
  });
});
